package file.day9_20;

public class Test01 {
    public static void main(String[] args) {
        String str = "张飞";
        int a = 3;
        int b = 2;
        str = str + a;
        int c = a + b;

        int[] as ={1,2,3,4};
        System.out.println(as[5]);


        Boo bs = new Boo();
        Score obj2 = bs;
        bs.getScore();

        String name[] = {};
        String[] name2 = {};                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                    ;

        Aoo b2= new Boo();
//        System.out.println(b2.num);
        Score obj = (Score) b2;//子类实现接口，要强转；
        obj.getScore();
     }
}
class Aoo{

    public Aoo(){
    }
    static void run(){

    }
}

class Boo extends Aoo implements Score{
    static int num = 12;
    public int getScore(){
        return 30;
    }
    static void run(){

    }
}
